diff --git a/README.md b/README.md
index 00e3054..057c389 100644
--- a/README.md
+++ b/README.md
@@ -1,30 +1,54 @@
 # Twik
 
-TODO: Write a gem description
+This gem is a ruby version of [Twik](http://gustavomondron.github.io/twik/) for Android.
+It is an easy to use password generator and manager.
 
 ## Installation
 
-Add this line to your application's Gemfile:
-
-```ruby
-gem 'twik'
-```
-
-And then execute:
-
-    $ bundle
-
-Or install it yourself as:
+Install it yourself as:
 
     $ gem install twik
 
 ## Usage
 
-TODO: Write usage instructions here
+### CLI
+
+```
+Usage: twik [options] tag
+
+Specific options:
+    -l, --length LENGTH              length of generated password (4-26). Default: 16
+    -p, --profile PROFILE            profile to use. Default: 'default'
+    -t, --type TYPE                  type of password:
+                                       alphanumeric_and_special_chars, alphanumeric, numeric
+                                       Default: alphanumeric_and_special_chars
+
+Common options:
+    -h, --help                       Show this message
+        --version                    Show version
+```
+
+Your profiles and private keys are stored in `~/.config/twik/config.yml`.
+
+### Gem
+
+```ruby
+require 'twik'
+
+Twik::TYPE
+# => [:alphanumeric_and_special_chars, :alphanumeric, :numeric]
+
+twik = Twik.new('PRIVATE-KEY', length: 16, type: :alphanumeric_and_special_chars)
+twik.generate('tag', 'masterkey')
+# => "ucf+p5TxMb0f/DE1"
+
+twik.generate('tag', 'masterkey', length: 8, type: :numeric)
+# => "91454552"
+```
 
 ## Contributing
 
-1. Fork it ( https://github.com/[my-github-username]/twik/fork )
+1. Fork it ( https://github.com/gdott9/twik/fork )
 2. Create your feature branch (`git checkout -b my-new-feature`)
 3. Commit your changes (`git commit -am 'Add some feature'`)
 4. Push to the branch (`git push origin my-new-feature`)